Q7: 2.5 mol% H2S in ppm would be?
A. 2.5
B. 2,500
C. 250,000
D. None of the above
Q8: How many ppm 2.5 wt% H2S would be?
A. 2.5
B. 2,500
C. 250,000
D. None of the above
Q9: How many ppm is 2.5 g H2S dissolved in 1 litre of water?
A. 2.5
B. 250
C. 2,500
D. None of the above
Q10: How many mole% 3,000 ppmv H2S is?
A. 3
B. 3,000
C. 300,000
D. None of the above
Q11: How many mole% 3,000 ppmw H2S is?
A. 3
B. 300
C. 30,000
D. None of the above
D; None of the above; as 3,000 = 3,000 in 1,000,000, whereas percentage is per 100, which in this case would be (3,000/1,000,000)*100 = 0.3 wt%; mole% will also be same as it is equivalent to 0.3 g H2S/ 100 g H2S = (0.3/34) gmols of H2S/(100/34 gmols of H2S)
Q12: You have 7 boxes of balls (each ball weighing exactly 10 grams) with one box with defective balls (each one of the defective balls weigh 9 grams). You are given an electronic weighing machine and only one chance at it. How will find out which box has the defective balls?
Pick 1 ball from box 1, 2 balls from box 2 and so on. In total you will have 28 balls. If all of the boxes have good balls, then the total weight of these balls would be 280 [= 10 x (1+2+3+4+5+6+7)] grams.
If box 1 has defective balls, then the total weight should be 1 gram less than expected (only one ball weighing 9 grams). If box 2 has defective balls, then the total weight should be 2 grams less than expected (two balls weighing 9 grams).
So once you weigh the set of chosen balls, find out the difference between the total weight and the expected weight. The resulting number would represent the box number which contains the defective balls.